Siemens SIMATIC NET S7-300 Manual page 104

5 Configuring Communication Connections
Note
The term "connection" is also used here for UDP. Reason: During configuration
(just as in TCP) the communication partners are assigned to each other and
therefore logically "connected". In actual fact, with UDP there is no explicit
connection establishment between communication partners.
Amounts of Data
Refer to the manual /2/ supplied with the Ethernet CP for the number of
communication connections supported by the Ethernet CP. The number of
connections per station can be increased by adding more CPs.
The Ethernet CP can transfer the amounts of data shown in the table below per job
on one connection:
Table 5-1
Sending
Receiving
Notice
The transfer of more than 240 bytes of data is supported by the current CPs.
Older version CPs support data transfer with a data length of up to 240 bytes.
Please note the information in Section 7 and in the manual of the Ethernet CP.
A -104
ISO Transport ISO-on-TCP
8192 bytes 8192 bytes
8192 bytes 8192 bytes
S7-CPs for Industrial Ethernet Configuring and Commissioning
TCP UDP
8192 bytes 2048 bytes
8192 bytes 2048 bytes
Release 01/2007
C79000-G8976-C182-07